staging: comedi: ni_pcimio: (!foo) preferred over (foo == NULL)

Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/ni_pcimio.c

@@ -1183,19 +1183,19 @@ static int pcimio_auto_attach(struct comedi_device *dev,
 		return ret;
 
 	devpriv->ai_mite_ring = mite_alloc_ring(devpriv->mite);
-	if (devpriv->ai_mite_ring == NULL)
+	if (!devpriv->ai_mite_ring)
 		return -ENOMEM;
 	devpriv->ao_mite_ring = mite_alloc_ring(devpriv->mite);
-	if (devpriv->ao_mite_ring == NULL)
+	if (!devpriv->ao_mite_ring)
 		return -ENOMEM;
 	devpriv->cdo_mite_ring = mite_alloc_ring(devpriv->mite);
-	if (devpriv->cdo_mite_ring == NULL)
+	if (!devpriv->cdo_mite_ring)
 		return -ENOMEM;
 	devpriv->gpct_mite_ring[0] = mite_alloc_ring(devpriv->mite);
-	if (devpriv->gpct_mite_ring[0] == NULL)
+	if (!devpriv->gpct_mite_ring[0])
 		return -ENOMEM;
 	devpriv->gpct_mite_ring[1] = mite_alloc_ring(devpriv->mite);
-	if (devpriv->gpct_mite_ring[1] == NULL)
+	if (!devpriv->gpct_mite_ring[1])
 		return -ENOMEM;
 
 	if (devpriv->is_m_series)